Apparatus for forming one-piece plywood corner units



July`20, 1943. H. McGowAN APPARATUS FOR FORMING ONE-PIECE PLYWOOD CORNER UNITS Original Filed May 17, 1941 s m. m mi, T. ,Am 6 C M 0 l O @2f/MMM According to the quality of the center ply, the depth of the saw cutis adjusted so that the bers of the center ply will break, forming a bridging when the pre-channeled plywood sheet is steam treated and bent. This bridging will make a good bond with the glue and extender or cement used to reinforce the corner unit.

In forming my improved plywood corner unit, the pre-channeled plywood sheet is placed on the table I and the lgauge bar 9 is adjustedto position the groove 22 directly adjacent the outer face of the metal straight edge 2 on the forward edge of the table I. The threaded sleeves 8 are then actuated to bring the jaw 3 downwardly into clamping engagement with the upper face of the plywood sheet as clearly shown in Figure 4. V

The valves I8, I9 and 20 are then opened and live steam obtained from the boiler I6 enters the steam pipes I2 and I3. The openings I4 cause jets of live steam to impinge against the channeled portion of the plywood sheet 2 I, thereby thoroughly saturating the channeled portion of the plywood sheet with steam, whereby the outwardly projecting portion of the plywood sheet may be easily bent down against the vertical face of the angular metal piece 2 to dispose the portions of the sheet on opposite sides of the channel 22 at approximately right angles to each other, as shown in Figure 5, and this with very slight pressure. When the lower steam pipe I3 is swung outwardly away from the table, the softened plywood sheet may be bent down against the front face of the table.

By operating the valves I9 and 20, jets of steam may be emitted from either or both of the steam` pipes. While I prefer to use live steam, it is to be understood that the channeled plywood sheet may be heated and softened by any other desirable means for facilitating easy bending of the sheet.

Also, the plywood sheet may be bent to form a corner unit of any desired angular shape and I do not wish to limit myself to the forming of a 90 angle bend.

After the sheet of plywood material has been bent on the machine, it is removed from the table and placed in a jack (not shown) and the channel is then lled with a suitable ller such as a mixture of Weldboard glue and extender or any other binding cement, and when this Yis dry, the corner unit is ready for installatiomin the' manner fully disclosed in my aforementioned, co pending application.

It will thus be seen from the foregoing description that I have devised an apparatus that will permit the easy and ready bending of a piece of plywood material for forming an angular corner unit and due to its simplicity the apparatus can be manufactured and sold at a low cost.

While I have shown the preferred embodiment of my invention, it is to be understood that Various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention and the scopey of the appended claims.

Having thus described my invention, what I X claim is:

1. In an apparatus for forming angular corner units from pre-channeled plywood sheets, a table, a clamping jaw extending across the top of the forward edge portion of the table to secure a pre-channeled plywood sheet thereon, with the channeled portion of the sheet disposed outwardly adjacent the forward edge of the table, a slidably adjustable gauge bar arranged on the table for engagement with the rear edge of the plywood sheet on the table, guide means for the slidably adjustable gauge bar, and upper and lower perforated steam delivery pipes arranged above and Vbelow the channeled portion of the sheet and extending for the full length of the channel for discharging steam against the channeled portion of the sheet to soften the same.

p v2. In an apparatus for forming angular corner units Afrom pre-channeled plywood sheets, a table, a clamping jaw extending across the top of the forward edge portion of the table to secure a pre-channeled plywood sheet thereon, with the channeled portion of the sheet disposed outwardly adjacent the forward edge of the table, a slidably adjustable gauge bar arranged on the table for engagement with the rear edge of the plywood sheet on the table, guide means for the slidably adjustable gauge bar, and upper and lower perforated steam delivery pipes arranged above and below the channeled portion of the sheet and extending for thefull length of the channel for discharging steam against the channeled portion 0f the sheet to soften the same, the lower steam pipe being mounted for lateral swinging movement to permit the steam softened portion of the plywood sheet to be bent downwardly against the front edge of the table.

3. In an apparatus for forming angular corner units from pre-channeled plywood sheets, a table, means for securing the rear portion only of a pre-channeled plywood sheet thereon with the channeled portion of the sheet disposed outwardly of and adjacent the forward edge of the table, the free forward end portion of the plywood sheet extending outwardly from'the front of the table, and perforated steam pipes arranged above and below the channeled portion of the plywood sheet for spraying live steam against the top and bottom faces of the channeled portion of the sheet simultaneously to soften the same and permit angular bending of the free forward end p0rtion of the plywood sheet.

4. In an apparatus for forming angular corner units from pre-channeled plywood sheets, a table, a clamping jaw extending across the forward edge portion of the table, and adjustable gauge bar on the table for engagement with the rear edge of a plywood sheet placed on the table, said clamping jaw and gauge bar holding the rear portion of the plywood sheet on the table with the channeled portion of the sheet disposed outwardly of the forward edge of the table, and means for spraying live steam against the top and bottom faces of the channeled portion only of the sheet to soften the same and permit the angular bending of the free forward end portion of the plywood sheet.

HAROLD MCGOWAN. 

